Piston valve



Patented .ul'y 29, 1952 the-operation of the valve', said pistonyalv 4 port sleeve I8'f isjsnuglyi ftted constructeds 0th`at itwillnot be `ploclzed up-by 10 'valve' housing andjis provided with live water and dirt orgumme'dup by oil. Setsfo openn'g's'l 9` One set of these pnin 1 Aotlierobject is to"povid'e"'a' valv'th'at 'is' reiSU'rsfv/ tnjeacli grooveltofl'lf Afpistofr'r particularly-"Weir adapted: to control a flow" ofl is reciprqcablydispseqvvitmri @sportysie cof'pres'sedai alternately tdtwo Vco'nd'u'ts Where" The piston 20 "isexternally provide'dwith tw one is always` open to pressure 'and the other'is a1wayspentofexhaust.

Another'object isA to prvi'de"a va1ve"^thatjis`VY particularly well adapted for use with pneumati cally operated mechanism o f thetype's'hownffin United1stt'sjlatentV No: 2,394,234; yiss'ucdFeb; rua'ry" 5,1946;VA oijin United" States 'Patenti' No. 2,391,558;issudrebruary 12,'1946:

Vmission of air under pressure by way of conduits 39, 40 and 38, to the two ends of the valve housing 5. The two pilot valves and 31 control the exhaust of compressed air, by way of conduits 38, 4I, 42, 4 and 1, from the two ends of the valve housing 5.

The energizing of the pilot valves 34, 35, 36 and 31 is controlled through switch means, Fig. 3, that controls two circuits and that will alternately close one of said circuits and open the and the piston 26 is Vin the position shown in Figs. 1 and 2, thenthe next time the ratchet relay is operated it will energize the coils 45 of the pilot valves 35 and 36 and de-energize the coils 45 of the valves 34 and 35. This will reverse communication through the pilot valves as respects inlet and exhaust'ofair under pressure and leave the valves 43 in the positions in which they 'are shown in Fig. 3. Compressed air will then be admitted through conduit valve 36 and one ofthe conduits 38 to the end of the valve other circuit. As illustrative of one type of switch that will operate in this manner a switch, Fig. 3, designated generally by 46 and herein referred to as a ratchet relay is shown. This ratchet 1 relay 46 has two spring contactors 41 and 48 engaged by lobed wheels 49 and 50 on a common shaftEI. A ratchet wheel 52 on shaft A5I is engaged by a pawl 53 on an armature plate 54 that is pivoted at 55 and yieldingly held in an elevated position by a spring 56. An electromagnet 51 ls provided for moving the armature plate 54 downwardly each time the electromagnet is energized to thereby impart to the shaft 5I a movement sufcient to close the circuit controlled by one of the contactors 41 or 48 and to open the circuit controlled by the other one of said contactors. The electromagnet 51 is connected, as by conductors 58, with any suitable switch means by which the operation of the pneumatic cylinder I2 is controlled.

As diagrammatically shown in Fig. 3, one terminal of the coil of each pilot valve 34, 35, 36 andV 31 is connected by conductor means 59 with one conductor 6U of a source of supply circuit. The other terminal of the coil of each of the two diagonally opposite pilot valves 34 and 31 is connected by conductor means 62 with one terminal of the switch formed by the contactor 41 and the other terminal of this switch is connected by a conductor 63 with the other 'conductor 6I of the source of supply circuit. The two diagonally opposite pilot valves 35 and 36 each have the other terminal of their coil 45 Vconnected by conductor means 64 with one terminal of the switch formed by the contactor 48 and the other terminal of this switch is connected by the conductor. 63 with the conductor 6I of the source ofV energy circuit. i

Each time the ratchet relay 46 is operated it will energize the coils 45 of two diagonally opposite `.pilot valves and de-energize the coils 45 of the'other two diagonally opposite pilot valves. When pilot valves 34V and 31 are energized and opened then compressed air will be admitted through conduit39, valve 34 and one of the conduits 38 to the end of the valve housing 5 shown at the left in Figs. 1 and 2 and the end of the valve housing 5 shown at the right will communicate through one of the conduits 38, valve 31 and conduit 42 with the exhaust conduit 1. This will causethe valve piston 23 to bemoved into the. position shown in Figs. land 2. y In this position the piston 20 will establish communicationrom compressed air inlet port 6, through groove I5,

through passageway 2| around piston 20, and.; through groove I4 to the service pipe Ithat is connected with one end of the pneumatic cylinder'l2.V At the same timesaid piston 26 will open a passageway for the escape of exhaust air from the other end of cylinder I2 through groovel,

passageway 22, groove I1 and/conduits 4 and 1.

When the pilot valves 34 and 31 'are energized housing shown at the right in the drawings. At the same time the end of the valve housing 5 shown at the left will be opened to exhaust through one of the conduits 38, valve 35 and conduit 4I.

This will move the piston 26 to the limit of its movement to the left and establish communication to the cylinder I2 as follows: Air under pressure from inlet 6 will flow through groove I5, passageway 22, groove I6 and conduit II tothe right end of cylinder I2 and the left end of said cylinder I2 will be open to exhaust by way of conduit I6, groove I4, passageway 2I, groove I3 and exhaust conduits 4 and 1.

The pilot valves thus operate in pairs to control the movement of the piston 26 and the piston Vcontrols the inlet and exhaust of air to the device to be operated, such as the cylinder I2.v The passageways through the piston valve are of large size and liquids, such as water and oil, will pass through this valve freely without clogging the tial wall of said housing; a port sleeve of shorter i length than said housing closely tted therein;

live annular rows of perforations in said sleeve registering with with housing grooves respectively; two washer shaped bumper members disposed in the end portions of said housing and resting against the respective ends of said port sleeve; a centrally disposed inwardly projecting annular transversely notched bumper flange on each bumper; two caps secured to the respective end portions of said housing and supporting said bumper members: a port through each of said caps and bumpers; a piston slidably movable in said port sleeve, said piston having its end portions positioned for contact with the `notched iianges of saidr bumper members whereby Inovement of said piston is limited; two annular circumferential grooves on said piston providing on said piston two end head members of substantial length and a shorter medial head member, said piston grooves being of sufficient length to overlap two adjacent rows of perforations in said portV housing; and two service conduits through `said tubular vhousing connected respectively with the two annular grooves which are positioned'between the medial groove and the Vend grooves of said housing, whereby said' service conduits areV alternately communicatively connected with said iiuid pressure inlet conduit and said, iluid pressure exhaustV means by said piston grooves in re- 5 sponse to longitudinal movement of said piston Number in said port. sleeve. 622,165 WILLIAM J. MILLER. 696,847 ALFRED C. JOHNSON. 1,293,178 5 1,484,533 REFERENCES CITED 1,716,010 The following references are of record in the 251451977 le of this patent: UNITED STATES PATENTS 10 2,357,986 Number Name Date 2,409,517

465,232 Aiken Dec. 15, 1891 6 Name Date Phillips Mar. 28, 1899 Spencer Apr. 1, 1902 Osborne Feb. 4, 1919 Randall Feb. 19, 1924 Smeby June 4, 1929 Foster Feb. 7, 1939 Keelv May 9, 1939 Ray Jan. 18, 1944 Wchterman Sept. 12, 1944 Schmit` Oct. 15, 1946 

